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2018, Vol. 16, Special Issue 1

Selle kollektsiooni püsiv URIhttp://hdl.handle.net/10492/5379

Sirvi

Sirvi 2018, Vol. 16, Special Issue 1 Märksõna "alternative fuels" järgi

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  • Pisipilt
    Kirje
    Combustion property analyses with variable liquid marine fuels in combustion research unit
    (2018) Hissa, M.; Niemi, S.; Sirviö, K.
    The quality of ignition and co mbustion of four marine and power plant fuels were studied in a Combustion Research Unit, CRU. The fuels were low - sulphur Light Fuel Oil (LFO, baseline), Marine Gas Oil (MGO), kerosene and renewable wood - based naphtha. To meet climate change requirements a nd sustainability goals, combustion systems needs to be able to operate with a variety of renewable and ‘net - zero - carbon’ fuels. Due to the variations in the chemical and physical properties of the fuels, they generally cannot simply be dropped into existi ng systems. The aim of this research project was to understand how changes in fuel composition affect engine operation. The focus was on how various properties of the fuels impact on the combustion process – especially ignition delay and in - cylinder combus tion. The goal of the research project was to allow broad fuel flexibility without any or only minor changes to engine hardware. Before the engine tests, the CRU forms an easy and cost - effective device to find out the engine suitability of the fuel . The re sults showed that the ignition delay decreased expectedly with all fuels when the in - cylinder pressure and temperature increased. The differences in the maximum heat release rates between fuels decreased in high - pressure conditions. MGO had the shortest ig nition delay under both pressure and temperature conditions. Based on the CRU results MGO and kerosene are suitable to use in compression - ignited engines like the reference fuel LFO. In contrast renewable naphtha had a long ignition delay. If naphtha is us ed in a CI engine, the engine must be started and stopped with, e.g. LFO or MGO.
  • Pisipilt
    Kirje
    Kinematic viscosity studies for medium-speed CI engine fuel blends
    (2018) Sirviö, K.; Niemi, S.; Help, R.; Heikkilä, S.; Hiltunen, E.
    Engine - driven power plants, run by diesel fuel or gas, will be needed for peaking power to keep the electricity grids stable when the production of renewable electricity, e.g. utilizing wind or solar power, is increased. The choice of the alternative, renewable fuels for engine - driven power plants and marine applications is at the moment quite narrow. The amount of renewables of all liquid fuels is at present less than 2%. Biodiesels, FAMEs, have been studied for long time and apparently, despite of the problems they may have, they are still in the great interest. One import ant increment to the category of alternatives is fuels that are produced from e.g. oil wastes, i.e., recycled fuels. They are not renewable, but recycling of potential energy raw materials is still one step forward in increasing the suitable and more susta inable options. To utilize the blends in medium - speed engines for power production, accurate knowledge of the physical and chemical properties of fuel blends is very important for the optimization of engine performance. The determination of the fuel kinema tic viscosity is needed to create proper fuel atomization. The injection viscosity affects directly the combustion efficiency and the engine power. Consequently, this study focused on measuring kinematic viscosity curves for seven fuel blends, as well as t he neat fuels used for blending. The temperature range was 10 – 90 °C. The fuels used for blending were rapeseed methyl ester, animal - fat based methyl ester, hydro - treated vegetable oil, light fuel oil and marine gas oil produced from recycled lubricating oi ls.